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Help with vertical mounting solar panels

Ratbags

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Jan 16, 2021
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I'm in Bristol, UK. Roof mounting not feasible. Thinking to go vertical. Sun only gets to 11 degrees above horizon@winter solstice. Attitude is SSE facing. And yes, it does rain here a lot. (Last week it only rained twice: once for 3 days, and the second time for 4 days - an old joke).
I can go 4 metres wide and 1.7 metres high. The Sun on Dec 21 is only about 4 hours usable -- when it is clear.
Requirements: Run a full size fridge/freezer, iMac 27" 8 hours a day, 6 x 10W LED desk lamps, and a 3000 watt instant electric hot water shower for 15 minutes a day. Possibly also a 900w output room heater (1000 cubic feet) on really cold days - 20 per year - for a couple of hours per day. All of these currently run on 240v UK electricity, and are all fused 13A.
My simple question: Will it work if mounted 11 degrees from vertical to catch max. sun on that day?

No system as yet, seeing if any of you more knowledgeable folks can help with a simple question, which will probably be followed by many more, I am sure.
I think 3or4 x 24v 330 watt mono's, parallel only. Power Jack 8000w LF, 24v to 240v inverter OR Lvyuan 3000/6000 24v to 240v inverter, 24v battery bank, with lots of waterproof space to add additional batteries over time. Only need this set up to last 10 years, then transfer to Nova Scotia, Canada.
Without batteries: cost is about £1500 Sterling. With batteries: 10 x 12V 110AH LEISURE BATTERY, SLA(Calcium) 2s4p: cost is about £2200 Sterling

You will notice there is no charge controller in my list. What amperage would be best for the parameters I have set out?
Thanks. Hope this is enough info to make a reply.
 
First, you need to characterize all of your loads in terms of Wh/day. A kill-a-watt device can give you that information directly.

4 * 1.7 = 6.8m^2

6.8m^2 * 1000W/m^2 * 20% = 1360W MAXIMUM assuming you can populate the available area 100%.

From link #6 in my sig:

1610836471645.png

System info:

1610836600448.png

Results:

1610836660116.png

The AC energy is your MONTHLY production, and it factors in the weather reported by the weather resource in the second image.

December sees, 25/31 = 0.806 kWh/day meaning you can run your space heater for less than an hour and nothing else. Assuming your iMac uses about 100W, you could just power it for those 8 hours and nothing else. Full size fridge/freezer commonly take up to 2kWh/day, so you couldn't even run it for a whole day.

Your available panel area and your available solar energy are insufficient to power your loads in the winter time.

Using that resource, you can simulate multiple scenarios.
 
Thank you snoobler, for your reply, and all the resources to allow me to figure out if it works. It seems I definitely do not have enough space for my needs in the dead of winter. I'll just be beholden to the purveyors of electricity for a while longer, until I figure somewhere to put more panels around my postage stamp garden without irritating the neighbours. I'm sure that I will have many more questions in the future, but at least I have a start point. Re: fridge/freezer, it only runs for 16 hours a day, as it is on an auto-timer for when I am asleep. As yet - 5 years and counting - I haven't had any spoilage or defrosting. Thanks, again.
 
Regarding the panel installation, I would top-hinge so you can adjust the bottom of the panels out to optimize the sun angle. Also allows you to secure the panels vertical during bad weather or high winds.

For my golf cart mount I used common PVC pipe. Very easy to obtain, cut and fabricate. Plus is strong, the mount has survived all the road bumps and shakes with no failures. The hinges are conventional tees with male threads that perfectly slip-fit into the tees. All mounting points are double-wall strong at the glue joints. I also edge-bolted the panels together for additional strength.

Edit: since the wall faces SSE you can play with a hinged reflector on the NE mounting to bounce western light into the panels.
 

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Thank you snoobler, for your reply, and all the resources to allow me to figure out if it works. It seems I definitely do not have enough space for my needs in the dead of winter. I'll just be beholden to the purveyors of electricity for a while longer, until I figure somewhere to put more panels around my postage stamp garden without irritating the neighbours. I'm sure that I will have many more questions in the future, but at least I have a start point. Re: fridge/freezer, it only runs for 16 hours a day, as it is on an auto-timer for when I am asleep. As yet - 5 years and counting - I haven't had any spoilage or defrosting. Thanks, again.

Even if only allowed to run 16 hours per day, the actual energy usage is unknown. For planning purposes, a kill-a-watt meter or similar will allow you to see the actual energy use of a device.
 
Yes. I will have to invest in one of those before anything else. Thanks.
 
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